Question

When a body falls in air, the resistance of air depends to a great extent on the shape of the body. $3$ different shapes are given. Identify the combination of air resistances which truly represents the physical situation. (The cross sectional areas are the same)

1. Disc
2. Ball
3. cigar sheped

• A. 1 < 2 < 3
• B. 2 < 3 < 1
• C. 3 < 2 < 1
• D. 3 < 1 < 2

Answer 1

Answer: (C)

Fig. 3 is stream lined, so air resistance for it will be minimum. For fig. 1 surface area is maximum, so air resistance for it is maximum. Hence, correct sequence is $3<2<1$.